Oil filter



March 18, 1952 R, Q BECKETT 2,589,920

OIL FILTER Filed Dec; 15, 1947 fnl enl of Ronald C. Beckeff ,,-medium.-

Patented Mar. 18, 1952 OIL FILTER Ronald Carey Beckett, Galt, Ontario, Canada, as-

signor to Kralinator Products Limited, Preston,

' Ontario, Canada Application December 13, 1947, Serial No. 791,498

This invention relates to oil filters and more particularly to oil filters for use in pressure lubri- -cated systems and the principal object of the invention is to provide an extremely simplified and reliable filter unit whichwill function eifectively to filter foreign material from the oil but which will, upon rise of pressure in the unit beyond a predetermined permissible value due to increased circulating pressure or clogging of the filter element, automatically function to provide a by-pass passage circumventing the filter element until the pressure is reduced to prevent stoppage of circulation of the oil.

A further important object is to provide a readily manufactured'and economical filter unit which will employ a filter cartridge which can ment.

a A still further object is to provide a casing which will receive and support the filter cartridge without requiring the use of brackets or other holdingmeans.

The principal feature of the invention consists in providing an oil filter unit having a ported return fiow tube centrally arranged in a cylindrical casing and surrounded by a filtering medium to filter oil delivered under pressure to the casing and passing through the ports of the central return tube, the return tube being provided with a conical valve seat arranged above the filtering medium and with a spring-actuated conicalvalve slidably arranged there-in for .co-operation with the valve seat, openings being provided in the tube to provide communication between the casing and the interior thereof about the valve seat whereby oil entering the openings acts upon the conical periphery of the valve to exert an upward force thereon against its spring, the'valve being adapted upon increased-oil pressure in the casing beyond a predetermined permissible value to lift against its spring and to allow the oil to enter the central tube bye-passing the filtering medium.

' A further feature consists in providing means for adjusting the spring pressure acting on the valve to regulate the pressure at which the valve will operate.

A further-important feature consists in utilizing removable filter cartridge asflhe filtering 2 Claims. (Cl. 210131) A still further and important feature consists in forming the lower end of the casing with a plurality of circumferentially spaced concaved indents to define an internal seat to support the filter cartridge above a central sump arranged below thecartridge, and providing the casing with a removable cap held in place by a nut threaded onto the central return tube.

Referring to the accompanying drawings, Figure 1 is a side elevational view of my filter unit.

Figure 2 is a' vertical mid-sectional view of my filter unit shown in Figure 1.

With reference to the accompanying drawings', my filter unit comprises a cylindrical casing I having the lower end provided with a plurality of circumferentially spaced ccncaved indents 2 terminating in a reduced central orifice 3 and secured in this orifice is a centrally located tube'4 which extends upwardly beyond the open upper end 5 of the casing and is provided with an externally threaded end 6.

Adjacent the center the tube is provided with ports I leading to the interior thereof, and surrounding the tube is a filter cartridge 8 in the form of an outer perforated cylindrical wall 9 and, a concentric inner perforated cylindrical wall I!) having filtering material I I packed therebetween.

The walls 9 and II] are held in position by' annular end discs I2 which are provided with annulargrooves 13 to receive the ends of the walls.

The lower end plate or disc I2 has an annular angle member I4 secured to the inward side thereof adjacent the inner edge to form an annular channel to receive a gasket I5 of suitable compressible material.

Arranged in the tube 4 adjacent the upper end and immediately above the upper end of the filter cartridge 8 is a plug I6 provided with a central orifice I1 which tapers inwardly from its upper edge to form a tapered valve seat I8.

Slidably mounted in the tube 4 above the plug I6 is-a valve I9 formed'with a conical extension 26 to cooperate with the tapered valve seat I 8.

Extending from the opposite end of the valve is a. stem 2I which serves to locate a compression-spring 22 arranged between the valve and a plug 23 threaded into the upper tube end 6.

cap member 25 having a downturned edge flange 26 arranged to extend over the cylinder or cas ing end. The central portion of the cap member 25 is arched upwardly and is provided with a central orifice or opening 21 through which the tube 4 extends, and a nut 28 having an annular flange 29 intermediate its length is thread- To ensure that the filter cartridge 8 is held down firmly against the seat as formed'by the indents 2 the nut 28 carries a compressionqspring.

32 securedthereto and extending downwardly to engage and compress a suitable gasket 33 which surrounds the central tube 4 and-bears on the upward cartr dg dis I In operation oil enters the casin 5 under I pressure through a suitable inlet 3d and, after passing through the perforated cartridge walls 9 and 10 and inervening filtering material. ll, enters the port I in the central tube as clean oil and is conveyed away through the lower end of the tube- The gaskets l5.;and 33 located at the ends of the filter cartridge ensure that under normal operation none of the dirty oil entering the inlet enters the .spacebetween the central tube 4 and theiinner cartridge wall Iii-without first passing through the filtering media where the sludge and deposits carried are removed.

'In the event the ,filt er cartridge becomes p u ged or the oil is d livered int the casing I under excessive pressure the oil will not penetrate through the filter cartridge with sufiicient rapidity to maintain the proper flow out the lower end of the central tube and hence an abnormal pressure will be built up in the casing.

Since the oil in the casing has free access to the annular cuneiform chamber defined within the interior of the central tube 4 above the valve seat !8 through the openings 24, a pressure will be exerted on the conical thrust face of the conical valve extension 20, and this pressure may be resolved into an upward force tendi g to .lift the valve l9 off its seat against the action ofthe spring 22.

When the pressure in thecasing I exceeds a predetermined value, which is dependent upon the compression force of the spring and the angle of the conical face .of the valve extension 20, the valve will lift allowing the oil from the casing to flow through the opening 17 in the plug I6 into the interior of the tube 6 and out the lower end thereof to'preclude any possibility of a stoppage of the oil circulation.

In the arrangement shown with the upper plug '23, against which the upper end of the compression spring 22 abuts, threaded into the tubeend 6, an adjustment of the compression forceof the spring 22 may be madeby rotationof the plug '23 to adifferent position. Thus :acontrol of the pressure req ired to open -the-va1ve 19 is proaided- :In theevent that oil entering the upper end of theltube ,4 through theopeningsitil leaks past the valve [-9 into thecnamber formed between the upper-face of s'the valve :and the upper plug 23.

- ILPIGl/idfl; a: central orifice 135 through the-valve through which the trapped oil may escape into the lower portion of the central tube.

It will be appreciated that with the shape of the casing I provided with the contracted end the filter cartridge 8 can be quickly inserted into position and will rest on the indents 2 which form a seat to support the cartridge above a sump 36 where the heavier wastamaterialswhich sink down between the indents2 collect and are removed through the drain opening 31.

With this arrangement no separate brackets or other holding devices for supporting a filter cartridge need be provided and the spring 32 serves to securely hold the filter cartridge firmly against the lower casing end 2.

The whole element may be mounted on any suitable SuppQrt, .such as indicated at 38.

From the foregoing it will be appreciated that my filter unit can be readily and economically manufactured and can be quickly and readily assembled, and when it is necessary to replace the filter element it will .be --an extremely simple ma r to remove th cap mem er, repl eethe filter element andreplace thecap. 'lhusbyhaying the filter element removable and ofra relatively inexpensive .construction my-filter unit can be used indefinitely and the filter. elements changed as frequently as required to ensure proper filtering at an extremely lowcost. I

While my filter unitis particularly adaptedifpr filtering oil in forced lubricating ,systems,,,other liquids may be filtered using :the principle ofzmy unit and withoutdeparting from thescoperof my invention.

WhatI claim asmy inventionisz V1..In an voil filter unit, a longitudinally upright casing having .an oiljnletopeningjnthe wall thereof, a vertical tubeacentrallyarranged in and extending longitudinally, of said casing and communicating .at its lower. endwith theexterior of said casing to provide an .oil outletand having an upper end threaded interim ly andexteriorly, a cap engaging the threaded exterier-pf said tube to seal the upper end thereof, ;a.fl lter vcartridge surrounding said tube with the ends of said cartridge in sealing contact with: said' tube, said tube having ports-therein between the ends of said cartridge, a valve seatarranged in said tu di ent he upper endofsaidcartridge, .a conical valve member slidably-z :arranged in said tube'above ,said-valve-,seat 213011562112 thereagainst and formed to havexaclosesliding fit at its maximum diameter with the-:interiorof said tube to define an annular variable chamber of cuneiform section above said-valve seat with the inner wall thereof defined bysaid conical valve presenting'an angular upwardly diverging thrust surface, the outer. wallof saidchamber defined by said tuberhaving ports therein toestablish a pressuretoil' wedge in said chamber aeting on said angular-thrust surface to .liftsaid valve under force :of the vertical resolution .of the force of said oil wedge against: said angular thrust surface, an adjustable -plug.;threaded into the upper end of said tube,.andyaisprin jzinterposed between said adjustable. :plug :and valve and urging said valve,-againsk-said;valvewseat. said valve being provided-wit a bleed orifice therethrough.

An filter uniteemprisinean :uprisht cylin dr al cas ng havin an inlet openin there' in, an open upper end and a lower. rendiziormed "with ap ality of circumferential;spaced-r .-in-

dent d finin a seat-.abovean :cil rsumn; avertilongitudinally of said casing, said tube projecting at its upper end above the open upper end of said casing and communicating at its lower end with the exterior of said casing, a removable cap closing said upper casing end and having an opening therein through which said upper tube end extends, said upper tube end being interiorly and exteriorly threaded, a second cap engaging the threaded exterior of said tube to seal said tube and to engage the aforesaid cap to seal the open ing therein while clamping said cap in casingclosing relation, a valve seat arranged in said tube adjacent the upper end thereof, a conical valve arranged in said tube between said second cap and valve seat and snugly fitting said tube at its upper end and presenting a conical surface above said valve seat, an adjustable plug threaded into the upper end of said tube above said valve, a spring interposed between said adjustable plug and valve, a cylindrical filter element enclosing the central portion of said tube and seating on said seat defined by said indents and engaged in sealing contact at the ends with said tube, spring means for holding said filter element against said indents, said tube having ports arranged in the portion enclosed by said filter element and the portion immediately above said valve seat to permit oil under pressure to enter said tube from said casing and act against the conical surface of said valve to exert a force determined by the pressure of said oil and conicity of said presented valve surface. 7

r RONALD CAREY BECKETT.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,002,905 Dronsfield Sept. 12, 1911 1,036,479 Flamm Aug. 20, 1912 1,162,153 Gensceimer Nov. 30, 1915 2,188,745 Wagner Jan. 30, 1940 2,454,030 Besore Nov. 16, 1948 2,478,109 Kamrath Aug. 2, 1949 FOREIGN PATENTS Number Country Date 316,452 Great Britain Aug. 1, 1929 533,576 Great Britain Feb. 17, 1941 

